The foul odors associated with draft pulp mills is caused by reduced sulfur gases (TRS), primarily hydrogen sulfide, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide. The major sources of emission of these gases are the digester, the evaporator, and the recovery boiler. Smaller amounts come from other point sources such as the smelt tank and black liquor oxidation exhaust. TRS gases are neurotoxins. In high concentrations they are fatal. Their effects on humans at various lower levels of concentration range from respiratory irritation, susceptibility to viral infections, eye irritation and permanent visual impairment, nausea, mental confusion, and depression. Studies have linked longterm TRS exposure to permanent neurobehavioral impairment. (2) At least two studies have suggested a link between long-term low level TRS exposure and elevated suicide rates. (3) One of the most careful series of studies of the effect of kraft pulp mill TRS emissions on the health of residents living near such mills was conducted in Finland in the 1990's. Since TRS production is associated with draft mills whether or not chlorine bleaching is involved, these studies are relevant to Eureka exposure to Samoa mill air emissions.
The South Karella studies were conducted in southeast Finland by researchers from Johns Hopkins University and the University of Helsinki. Using standard epidemiological procedures, the Karella researchers distributors health surveys to randomly selected subjects in three communities where actual air testing demonstrated differing levels of ongoing pulp mill TRS exposure. Daily variations in TRS concentrations were also recorded. The results of these studies showed a positive correlation between elevated TRS levels and increased mean intensity of headache, depression, tiredness, and nausea. A similar correlation was found between TRS levels and acute respiratory infections, as well as respiratory symptoms and eye symptoms. These results were found at relatively low levels of exposure. In the Conclusion discussion of a 1998 Karella study report the author states, "The present study strengthens the evidence that long-term exposure increases respiratory tract symptoms at far lower levels than could be expected from current knowledge of the toxicology of these compounds."(4)
The exact amount of TRS exposure produced by any pulp mill is difficult to assess accurately. As the 1998 report quoted above remarks of the mills included in the Karella study, "-a typical exposure profile near the pulp mills was characterized by short-term peaks between periods of no or low exposure." For this reason short of constant mobile monitoring, statements regarding TRS emissions from a particular mill are, necessarily, educated estimates. Given this caution, however, annual pulp mill TRS emissions are almost always to be measured in tons. What about the Samoa mill? The last estimate for the mill I saw was 24 tons annually; that's 48,000 pounds of neurotoxin poison a year. (5)
(1) Jaakkola JJK, Marttila O, Vikka V, et al. "The South Karella Air Pollution Study: the effects of malodorous sulfur compounds from pulp mills on respiratory and other symptoms". AM REV RESPIR DIS 1990; 142:1344-50.
Haahtela T, Marttila O, Vikka V, et al. "The Karella Air Pollution Study: acute health effects of malodorous sulfur air pollutants released by a pulp mill. AM J PUBLIC HEALTH 1991; 82:1060-63.
Mattila O, Jaakkola JJK, Vikka V, et al. "The South Kerally Air Pollution Study: the effects of malodorous sulfur compounds from pulp mills on respiratory and other symptoms in children". ENVIRON RES 1994; 66:152-59.
Mattila O, Jaakkola JJK, Partti-Pellinne K, et al. "The South Kaarella Air Pollution Study: daily symptom intensity in relation to exposure levels of malodorous sulfur compounds from pulp mill production". ENVIRON RES 1995;71:122-27.
Partti-Pellinen K, Marttila O, Vikka V, et al. "The South Keralla Air Pollution Study: low-level exposure to malodorous sulfur compounds as a determinant of eye, respiratory and central nervous symptoms in adults". ARCH ENVIRON HEALTH 1998; 51:315-20.
(2) Kilburn KH< Warshaw RH. "Hydrogen Sulfide and Reduced-Sulfur Gases Adversely Effect neurophysiological Functions". TOXICOLOGY AND INDUSTRIAL HEALTH 1995; 11(2): 185-197.
(3) Report by Dr. R H Weisler, University of North Carolina School of Medicine to the 18th Annual U.S. Psychiatric and Mental Health Congress in Las Vegas, November 2005; also prior Weisler study presented to the 17th Annual U.S.. Psychiatric and Mental Health Congress, 2004, and the National Institute of Mental Health New Clinical Drug Evaluation Unit, June 2005.
(4) Jouni J K Jaakkola. "The South Karella Air Pollution Study: Changes in Respiratory Health in relation to Emission Reduction of Malodorous Sulfur Compounds from Pulp Mills". Archives of Environmental Health; July 1999.
(5) Document Dated 8/21/2006; Subject: Evergreen Pulp Title V Permit Application, Submittal of Additional Requested Information; To Simona Altman (NCAQMD), From Carol Romero (Evergreen Pulp), Attachment B.